Precipitating apparatus of cyanid solutions.



D. BOSQUI.

PREClPITATING APPARATUS FOR OYANID SOLUTIONS.

APPLICATION I 'ILED DEC. 9, 1911. 1,035,941.

Patented Aug. 20, 1912.

- 2 SHEETS-SHEET 1.

WITNESSES fi DANIEL BOSQUI? I BY WAX/l4 'M/z/ MM His ATTORNEYS.

Patented Aug. 20, 1912.

APPLICATION FILED D1109, 1911.

2 SHEETS-SHEET 2.

WITNESSES INVENTORV mum BOSGUL BY I'Mj H i 3 ATTORNEYS LMA/0M.

"DANIEL Bosaur, or monnnnmgwnsnmeron, ASSIGNOB, 'ro MnnnILnME'rALLUnamen COMPANY, a conron'arron or canrronmn.

PBECIPITATING APPARATUS FOR CYANID SOLUTIONS.

I Specification of Letters Patent, Application filed December 9, 1911. Serial No. 664,744.

Patented Aug. 20, 13912.

To allwhom it may concern.

Be it known that I, DANIEL Boston, a citizen of the United States, and a resident of Mona-ban, county of King, State of Washington, have invented certain new and use -ful Improvements in PrecipitatinglA para- -tus for Gy'anid Solutions, of whic t been determined, may be set to insure the fixed predetermined time contact. I

Another object of the invention is to provide means for either intermittently or continuousl carrying on the precipitating process y the use of one'vessel or receiver.

Another object of the invention is to pro.- vide means for addlng a predetermined 'quantity of precipitant to a given amount of solution in a containing vessel and discharging the mixture of solution, precipitant and precipitate from the vessel after a certain predetermined time of contact.

' Another object of the invention is to provide a precipitating apparatus by means of which the mixture -of cyanid solution and precipitant may be agitated without entrainmg any air in the mixture.

A further object of the invention is to provide a precipitating apparatus in which the larger and heavier particles of the precipitant are recirculated throu h the cyanid solution with the eifect of re ucing the diameter of these particles and obtaining an increased efl'ect thereof onthe solution.

In practice, metallic zinc-bearing materials or other metalliferous preclpitants have heretofore? been used to recipitate metals from c anid solutions an the most ractical resu ts have been obtained in a closed receptacle or in such mannerthat the air has been excluded from the mixture of solution, precipitant and precipitate and subsequently conducting the mixture withbut additional agitation through a filter.

By thismethod, however, it is dificult to adjust or prolong the contact between the solution and precipitant in accordance with the requirements of solutions low in cyanid content.

In practice zinki'ferous-precipitants have been used to precipitate cyanidsolutions in the following ways. Said precipitants have been added-to'the solution and the mixture agitated usually by compressed air, and 00-' casionally by mechanical stirrers. In either event an entrainment of material amounts of the oxygen of the air has resulted, which oxy en is a serious deterrent to the most.

eflicient precipitation, which is a reducing reactlon. For the purpose of best'obviatin'g this oxygenation, metalliferous precipitants have been added to the solution in a closed circuit and the mixture conducted without rest, without exposure to the atmosphere, and without prolonged agitation toa closed filter. In the latter method, however, it is 'diflicult to adjust or prolong the contact between the solution and precipitant, which prolonged and adjustable contact is desirable when the solutions are low in strength orotherwise feeble in activity toward the precipitant.

, In the present apparatus the'time of contact of the preci itant with the solution may be prolonge and regulatedto obtain the best results, dependingupon the circumstances of operation, and the precipitant may be re-circulated through the solution so that it iscontinually brought into effectime contact with the solution withoutsubjecting the mixture ofisolution, precipitant and precipitate tothe deleterious efiects of entrained air, as is the case when thesurface of the mixture is markedly agitated by means of mechanical agitators or when the mixtureis agitated by com ressed air.

The apparatus possesses 0t er advantageous features, which, with the foregoing 'will be set forth at length in the following description, where I shall outline in full that form of embodiment of the invention which I have selected for illustration inthe drawings accompanying and forming part of the present specificat1on.. The novelty of the invention will be included in the claims succeeding said description. From this it will be apparent that I donot restrict myself to the showing made by such drawings and description as I may adopt many variations tant to the solution in the tank, means for agitating the mixture without entraining any air therein and means for automatically opening the discharge outlet after the mixture has been agitated-for a predetermined time. Means may also be. employed for automatically cutting off the flow of solution into the tank as the. discharge outlet is opened.- I 1 Referring to the drawings :.Figure 1. is a side. elevation of the apparatus showing the tank in vertical section, the apparatus being arranged for continually carrying on the precipitating process. 'Fig. 2 is a similar new of a modified form ofthe apparatus in which the process is carried on intermit-.

tently. Fig. 3 is' a top or plan view of the apparatus as'shown in -Fig. 1. Fig. 4is. a top or plan view'of the apparatus as shown in Fig. 2. Fig.- 5 is anelevation showing. the collecting tank which is used in con.-.

nection with the apparatus shown in Fig. 2 in which the precipitating operation is carried on intermittently; Fig. 6 is a detail of the connections between the discharge controlling float and the discharge controlling mechanism.

The solution to be precipitated is conve ed 'to the receiving tank 2 through the con uctor '3' which ism connection with the source of supply. In the apparatus shown in Fig.

' 1 this conductor extends downward into the 'receiving tank- 2, preferably to such die.-

tance, that at all times during the operation of theapparatus the solution is discharged below the surface of themixture therein. This construction prevents the entraining of any air in the mixture and consequently obviates the deleterious effect of; entrained alr. Y

As shown in the drawing the discharge outletof the tank is closed, and on account of the inflow of solution through the conductor3, the-level of the liquid in the tank rises. As the level of the liquid approaches .the filling point of the tank, predetermined by the length of contact required for the precipitant, preferably zinc dust, to be supplied thereto, the liquid acts against the float 6 suspended within the tank and raises the same, the stem 7 of which float works through a guide 8 clamped to the inner end of a tilting lever 9. The position of the float within the tank is adjustable so that the zinc dust may be added to the solution at a certain predetermined time depending upon the characteristics of the solution. The

lever 9 consists of a tubular rod or. pipe, partly filled withquicksilver and supported centrally on the journal 10. To the stem 7 are secured, above and below the guide 8, the collars 11, which are adjustable on the stem, the lower one of which on the upward movement of the float 6 raises the inner end of the pivoted or tilting lever 9. Attached to said lever andprojecting upwardly centrally therefrom is ajforked arm 12, the free ends of which, depending on the upward or downward movement of the float 6, engage with apin 13 projecting laterally from a horizontally slidable arm 14 and moves the same inwardly or outwardly. This slide armcarries the cutter blades 15 and 16,

15 for a slight distance, about one half of an inch, so that when the blade 16 makes its re-. turn stroke from within the box 17, the same movingin unison with the blade 15, no zincdust feeds out, of the box.

As the inner end of the-lever 9 is carried past the horizontalby the uprise of the float 6, thequicksilver-contained. therein flows to the opposite end of the tube-lever 9 and the forked a'rm 12, attached tosaid lever impingesjbn the pin or stud13 and shifts the arm 14 to move the cutter. blade 16 within the feed box 17 and the cutter blade 15' from within the same, allowing the zinc dust to drop from within the feed fox into the solution contained Within the'tank, the amount or charge of the zinc dust depending upon the. inside measurement of the feed box 17 and the distance that the cutter blades 15 and 16 arespaced apart. The amount of z'incjdust contained in one charge, is the amount-which. has been found by previous operations to be sufiicient to meet the requirements of operation. To the bottom of the feed box I preferably attach a canvas chute .4 which extends downward into the tank to a point slightly belowthe bottom of float 6. The lower end of the chute will therefore be immersed in the liquid before the zinc dust is dischar ed from the feed box, and the zinc dust will-be conducted 'directly under the surface of the liquid, with very slight agitation of the surface of the liqui' As the liquid in. the tank rises it raises the float 18 attached to the stem or rod 19 which is slidable vertically through the slidable bearing 41 supported in the bearings 42. A pin 43 on the slidable bearing is engaged by a fork 44, attached to the end of the lever 21 pivoted at theto of the tank. As the liquid in the tank reac es the filling point thereof, a collar" 22 on the rod 19 bears against the lower 'end. of the bearin 41, moving it'upward and consequently tilting the lever The lever 21 ispreferably centrallypivoted, and formed of a hollow rod or tube partially filled with quicksilver .for

' the same reasons as lever 9.

a stem 28 projecting from the controlling valve 29 situated within the discharge pipe 30', consequently when the upper collar acts against the inner end of the lever on the downward movement thereof, the same is'carried therewith and its outer end thrown upwardly, -drawing therewith the'stem 28 and raising or unseating the valve 29 to perany condition speed.

mit the .discharge of the mixture from the tank through the discharge pipe 30, permitting the mixture to be conducted to the filter 51.

The'diameter "of the discharge pipe 30 is preferably larger than the diameter of the inlet pipe 3, and with the aid of a pump, not shown, the mixture is discharged from the tank much more quickly than the solution enters, so that the level of the liquidin the tank falls. As the level is lowered, the

float 18 and the rod 19 move downward.-

Arranged'on rod 19 near the upper end thereof is a collar 23, which at the proper time in the discharge of the tank acts against the top of the bearing 41 moving it downward and causing the lever to tilt to close the valve 29. The collars 22 and 23 are adjustable upon the rod 19 so that the time of opening and closingthe vdischarge valve may be regulated and fixed to meet thetank was fallingthe float 6 hadoperated to tilt the lever 9 and place the precipitant feeding apparatus in proper position to be again actuated by the rise of theliquid.

Within the tank is located an agitator 33, which is carried by the vertical shaft 34. The tubular radial arms of the agitathe liquid in tor, are provided with depending incllned nipples-33 and the agitator is connected by a pipe 34 to a centrifugal pum 35, which takes liquid from within the tan by means of a suction pipe 35. The liquidv thus drawn from the tank is forced by the centrifugal pump 35 back into the hollow armed agitator 33 through the pipe 34, the pressure of the liquid thus forced into the agitator escapes through the nozzles 33 cansing the agitator to be rotatedat a suitable The disposition of the nozzles or nipples 33' relative to the tubular arms is such, that at each complete revolution of to said rod above and below of operation. As the level ofthe agitator the discharge from the nozzles or nipples, which are arranged at an angle to the bottom of the tank, sweeps the entire surface of the bottom.

' The disturbance'of the mixture caused by the agitator is such that the upper surface thereof is notmarkedly affected thereby and remains placid after it has reached the level at which the precipitant is deposited in the solution. Y

The jets of liquid striking the bottom ofthe tank preventauy settlement of the precipitant of precipitates. Through the agency of the agitator an agitation of the mixture is maintained that brings the zinc dust particles and the pregnant solution into intimate, recurring and prolonged contact,

and the circular motion of the tubular arms gives a rotary movement to the solution *hile the jets of discharge create anupward 1rrent of the mixture, all tending to prouce perfect agitation and at the same time admitting or 'entraining no tion. I

When the-zinc dust is added to the solution, it sinks to the botto'm where it is stirred up and mixed with thejsolution by the agitator, a portion of the zinc dust and particularly the heavier and larger particles thereof which have a greater tendency to settle to the bottom are continuously drawn from the tank with the solution passing through the pump and are discharged into the solution in the tank from the agitator nipples. This re-circulation of the precipitant causes an intimate recurring and prolonged contact with the pregnant solution and assists in producing a substantially'complete and perfect precipitation. Furthermore, by this re-circulation, the diameter of these heavier and coarser particles is reduced by contact with the solution and greater amount of precious metals is precipitated.

In that construction of apparatus wherein the process is to be carried on intermittently, some means must be employed for cutting off the inflow of the solution into the tank when the discharge is opened. In this construction also, the inlet pipe need only extend downward into the tank to a point slightly below the level of the float 6, in order to cause the solution to enter the mixture in the tank below the surface thereof. A collecting tank 36 of larger capacity than the receiving tank should also be pro-' vided for receiving the solution from the source of supply and collecting the same,

air to the solua correspondingly during the time that the inlet valve is closed. 7

v 46. As the discharge valve is opened the inlet valve is closed and as the inlet valve is opened the discharge valve is closed, all of which operations are erformed automatically by the rise and all of the liquid in the tank beyond certain levels.

By the use of the described apparatus there is a positive ,feed of a predetermined quantity of zinc dust to a given quantity of cyanid to be precipitated, the flow of the solution for a single charge of the zinc dust therefor being automatically controlled, a positive time contact for'the zinc dust with the solution is provided, which may be va ried according to the requirements of the solution to be precipitated and in individual cases may thereafter be fixed. At the same time the mixture is maintained in a continuous agitated condition during the entire operation 0 precipitation and the precipitant is re-circulated through the mixture Without subjecting the mixture to the oxidizing effects of entrained air.

. By predetermined in this specification is meant predetermined ina practical sense as metallurgically applied to the operation of reduction Works. For instance, a predetermined amount of zinc dust means the amount which has been found by previous operations to be sufiicient to best meet the requirements of the general operation of the plant. Similarly, predetermined time of contact means that period which experience has demonstrated gives the best avera e results, all things considered, for the e cient and economic operation of the works.

I claim:

1. A precipitating apparatus comprising a receiving vessel for the solution and precipitant and means for adjusting the apparatus to vary the time of contact of solution and recipitant and for fixing the apparatus in adiusted positions.

2. A precipitating apparatus comprising a receiving vessel for the solution, means for adding a predetermined amount of precipitant to. said solution and means for adjust ing the apparatus to vary, the time of contact of solution and precipitant and for fixing the apparatus in adjusted positions.

3. A precipitating apparatus comprising a receiving vessel for the solution, means ac-. tuated by the rise of solution in the vessel for adding a predetermined amount of precipitant thereto, and means for adjusting the apparatus to vary the time of contactof said solution and precipitant and for fixing the apparatus in adjusted positions.

4. A precipitating apparatus comprisinga receiving vessel for the solution, means actant to said solution,.a float within the vessel for operating said feeder on the solution reaching a given level, means for varying the level at which said feeder is operated and means for discharging the mixture after a predetermined time contact.

6. A precipitating apparatus comprising i a receiving vessel for the solution, means for feeding a predetermined amount of precipitant to said solution at a predetermined time .inthe filling of the vessel, a valve controlled outlet to said vessel, means for operating said valve on the mixture reaching a given level. and means for varying the level at which said valve is operated.

7. A precipitating apparatus comprising a receiving vessel for the solution, means for feeding a predetermined amount of precipitant to said solution, a valve controlled outlet to said vessel, automatically operated means for opening said valve after a predetermined time of contact of the solution and precipitant, and means for adjusting the apparatus to ,vary said time of contact.

8. A precipitating apparatus comprising a receiving vessel for the solution, means for adding a predetermined amount of precipi-- tant to said. solution, a valve controlled outlet to said vessel, a float in said vessel for operating said valve on the mixture reaching a given level, means connect-ing said float with the valve operating mechanism and means for adjusting said connecting means for varying the level at .which the float actuates the valve operating mechanism.

9;]A precipitating apparatus comprising a receiving vessel for the solution to be pre-- cipitated, means for conducting thesolution to said vessel, means operated by the rise of the solution in the vessel for supplying a charge of precipitant to the solution in said.

vessel, means for agitating the mixture and means automatically thrown into action for controlling the discharge of the mixture from the vessel.

10. A precipitating apparatus comprising a receiving vessel, means for conducting the solution to said vessel, means operated by the riseof solution in the vessel for supplying a charge of a precipitant thereto, means for agitating the mixture and means oper-' ated by the further rise of the mixture for controlling the discharge of .the mixture from the vessel.

11. .A precipitating apparatus comprising a receiving vessel, means for conducting the solution to said vessel, means for automatically adding a predetermined charge of precipitant to said solution, means for. agitating the mixture, and adj ust-able means for automatically discharging the mixture from said vessel after a predetermined time of contact of the precipitant and solution.

12. A precipitating apparatus comprising a receiving vessel, means for conducting the solution to said vessel, an automatically operated precipitant 'feeder for delivering a predetermined chargeot precipitant to said solution, a float within the. vessel for oper ating said feeder on the solution reaching a given level, means for agitating the mixture in the vessel, a discharge outlet to said vessel and means operated by the further rise of the mixture in the vessel for controlling said outlet. I

13. A precipitating apparatus comprising a receiving vessel, for-the solution to be precipitated, means for conducting the solution to said vessel, a plurality of floats within said vessel, an automatically operated precipitant feeder for charge of precipitant, arrangedto be operated by one of said floats on the solution.

reaching a given level, a valve controlled discharge outlet to said vessel, and connections between said valve and the second float for operating said valve as the level of the mixture in the vessel reaches a certain predetermined height. a 1

14. A precipitating apparatus comprising a receiving vessel having a valved outlet, means for supplying solution to said vessel, means operative by the rise of solution in the vessel for adding a predetermined charge of precipitant thereto, means for agitating the mixture and means for automatically controlling the valved outletconsisting of a float andmechanism connecting said'float with the valve for opening and closing the valve as the level of the mixture in the-vessel reaches certain predetermined upper and lower limits.

15. A precipitating apparatus comprising a receiving vessel, means for conducting the solution to said vessel, means for supplying a precipitant to said solution, means for agitating the mixture and means automatically thrown into operation for controlling the discharge of the mixture from the ves-' sel and the inflow of the solution thereto.

'16. A precipitating apparatus comprising a receiving vessel, means for conducting the solution to be precipitated to said vessel, automatically actuated means for supplying a predetermined charge of precipitant to said solution, means for agitating the mixture and automatically actuated means for controlling the discharge of the mixture from said vessel and the inflow of solution thereto.

delivering a predetermined 17. A precipitating apparatus comprising a receiving vessel, means for conducting the solution to be treated to said vessel, an automatically operated precipitant feeder for delivering a predetermined charge of precipitant to said solution, a float within the vessel for operating said feeder onthe solution reachinga given level, a discharge outlet to said vessel, and means operated by the further rise of the mixture in the v ssel for opening the discharge outletand stopping the inflow of solution to said vessel.

18. A precipitating apparatus comprising a receiving vessel for the solution to be precipitated, means for conducting the solution to said vessel, a plurality of floats within "said vessel an automatically operated precipitant feeder for delivering a predetermined charge of precipitant to said solution arranged to be operated by one of said floats on the solution reaching a given level, a valve controlled discharge outlet to said vessel, connections between said valve and the second float for operating said valve as the level of the mixture reaches a predeterminedheight, and means for simultaneously controlling the inflow of'solution into the vessel.

19. A precipitating apparatus comprising a receiving vessel having a valved outlet, valve controlled means for supplying solution to said vessel, means operative by the I rise of solution in said vessel for adding a predetermined charge of precipitant thereto, means for agitating the mixture and means for automatically controlling the valved inlet and outlet consisting of a float and mechanism connecting said float with said valves for operating the valves in opposite directions as the level of the mixture reaches certain predetermined heights.

' 20. A precipitating apparatus comprising a receiving vessel, means for supplying solution thereto, means for adding a predetermined charge of precipitant to said solution,

means for agitating the mixture in the ves-- sel, automatically operated means for controlling the discharge of the mixture from said vessel, a filter, and a conductor for conducting the mixture to said filter.

21. A precipitating apparatus comprising a receiving vessel for the solution and precipitant and means for'agitating the mixture by withdrawing the mixture from the vessel at a point adjacent to the bottom and forcing it back into the vessel below the level of the mixture therein through a closed circuit, all the parts of said circuit being normally located below the liquid level in the vessel.

22. A precipitating apparatus comprising a receiving vessel forthe solution and pre- 'cipitant, a closed circuit opening at both ends into said vessel adjacent the bottom, all parts of the closed circuit being normally receivingvessel for the solution and precipitant, a pump, and suction and discharge pipes therefor opening into the vessel adjacent the bottom,

said pipes forming a closed circuit whose parts are all normally located below the liquid level in the vess'el. v

24. A precipitating apparatus comprising a receiving vessel, a conductor for supplying solution thereto, means for supplying a predetermined charge of precipitant 'to said solution, means for agitating the mix- .ture'within the vessel, comprising a pump and suction and discharge pipes therefor entering the vessel adjacent the bottom thereof and automatically operated means for controlling the inflow of the solution and the discharge of the mixture actuated 25. A precipitating apparatus comprisinga receiving vessel having valve controlled inlet and discharge passages, automatically actuated means operated by the level of the solution reaching a certain point for supplying a predetermined charge of precipitant, means for agitating the mixture in the receptacle without entraining any air in the mixtureand means actuated by the further riseof the mixture Within the vessel toa certain level to open the discharge outlet and close the inlet passage.

In testimony whereof, I have hereunto set my hand at Issaquah, King (30., Washington, this 28th day of November, 1911.

DANIEL BOSQUL 

